1. Field of the Invention
This invention relates to an apparatus for generating acetylene gas in an exothermic reaction, indicated by the formula: ##STR1## The generation of acetylene gas provides a convenient fuel supply for a variety of purposes, including welding of metals, primary and secondary space heat, illumination and power for internal combustion engines.
2. Prior Art
The mixing of water with metallic carbides to produce acetylene gas is well known in the prior art. Prior to the use of electric power on automobiles, carriages commonly used carbide lamps for illumination. Typically, water was stored in a small chamber behind a reflector and was allowed to drip into a lower chamber containing calcium carbide (CaC.sub.2). Gas emanating from the calcium carbide was permitted to escape through a burner nozzle located between a lens and reflector. While not quite up to the illumination quality of a modern quartz-iode headlamp, these early devices gave ample illumination, using an easily-stored fuel. Similarly, several apparatus have been developed which provide for the generation of acetylene gas within cooled chambers. In one device, represented by U.S. Pat. No. 535,944, acetylene generators are nested within tanks containing cooling water which absorb the heat set free by the exothermic reaction of calcium carbide.
The provision of grids for holding carbide material in acetylene generators is also known. For example, a device, represented by U.S. Pat. No. 638,448, uses a cage-like arrangement for containing carbide material within a chamber of a gas-generating device. It is also known to provide cloth material around carbide briquettes in order to disperse water about briquettes of calcium carbide. In that case, the carbide is allowed to bunch together, as the cloth material provides no support structure which would prevent such bunching together.
There have been proposals to utilize gas produced by water-carbide reactants in order to propel motor vehicles. For example, one device, proposed in U.S. Pat. No. 4,054,423, uses pressure regulation to control the flow of both gas and water in a generator for propelling a vehicle. It is also proposed that the assembly be used in combination with a liquid (gasoline) fuel supply. Especially in the case of motor vehicles, it is important to provide an output of acetylene gas which can be closely controlled in accordance with the required power consumption of the vehicle. For this reason, a rapid interdispersion of reactants is important. In the case of the carbide-water system, this means that water must be allowed to rapidly disperse throughout the carbide "charge" (that carbide which is to be potentially exposed to water). In order to obtain such dispersion, it is important that the water by evenly distributed to the charge and that the charge be supported in a manner such as to reduce the obstruction of water by successive layers of carbide.
Motor vehicles, particularly highway motor vehicles including trucks and cars, are characterized by their varying requirements for power. The criteria for selecting a power plant are based on the desire to provide ample power, thereby enhancing the power performance of the vehicle, while reducing waste of power to maximize the fuel efficiency performance of the vehicle. For maximum economy, there is an optimum power capability for obtaining a specified power output from an internal combustion engine. While the figure may vary, the optimum power output for typical fuel injected spark- and compression-ignition engines is obtained at between 3/4 and full throttle applied at low engine speeds. This makes the use of a relatively low-powered power plant advantageous in terms of fuel economy. The minimum size of a power plant is determined primarily by three design criteria: maximum acceleration requirements; maximum speed; and ability to maintain speed in various adverse conditions such as in climbing hills. Of these criteria, the ability to accelerate and the ability to climb hills is usually a transient occurrence, i.e., not experienced for extended periods of driving. Maximum speed at cruise, on the other hand, can be required for considerable periods of time. In many cases, the maximum cruise speed criteria requires less engine power than the acceleration and hill climbing criteria. In other words, the engine is required to have more power than is necessary to maintain maximum cruise and therefore more power than is needed for its continuous operation. Since the increase of power capacity may result in a decrease in fuel economy, many vehicles have less economy than they would if their engines only were selected for their maximum cruise ability. Furthermore, the maximum speed for a vehicle may be substantially different from the anticipated average highway speed of the vehicle. For example, if it is anticipated that a vehicle will be cruising at 140 kilometers/hour in most conditions but it is desired that the vehicle be able to accelerate up to 200 kilometers, the economy at 140 kilometers may be compromised.